Metal end closure for container body



April 6, 19,65 A. P. zuNDEL METAL END CLOSURE FOR CONTAINER BODY FiledFeb. 28, 1962 mvENToR. .4E T//aPP/z/P .za/mez BY w@ @im Allow/.5v

United States Patent O 3 176 872 METAL END crostini; non CoNrAnsnn ironyArthur Philip Zundel, Cary, Ill., assigner to American Can Company, NewYork, N .Y.,` a corporation ci' New Jersey Filed Feb. 2S, 1962, Ser. No.176,280 4 Claims. (Cl. 22d- 54) The present invention relates to aneasily removable metal end closure for a container body. Moreparticilarly, it relates to a unique means of fastening a pull tabadjacent one end of a scored area within the metal end closure for easyremoval of that portion of the closure defined by the score lines.

Metal `end closures for container bodies, particularly tubular metal canbodies, which are adapted to be readily removed from the body by tearingout a scored area, are well known in the art. In general, the scoredarea in these prior `art metal end closures is defined by a first pairof substantially concentric score lines adjacent the seam joining theend to the body; and a second pair of score lines joined to the firstpair and extending inwardly towards the central portion of the end.Examples of such prior art are U.S. Patents 2,112,231 and 2,946,478.

The difference between vari-ous prior art disclosures over this generalconfiguration outlined above lies in their varying means of freeing theinwardly extending ends ot' the second pair of sco-re lines. While no seere technical problems exist in scoring the metal end closures in themanner outlined, the prior art has striven to simplify and improve theprocedures for providing means for freeing the inwardly extending end ofthe tear strip.

It is therefore an object of the invention to provide a new and improvedstructure for freeing one end of a tear strip in a metal end closure fora container.

Another object is to provide a means for freeing one end of a tear stripof the character described which involves a minimum of manufacturingoperations.

A further object is to provide a simple means for securely anchoring apull tab to one end of a tear strip of the character described.

Yet another object is to provide a means for anchoring a pull tab to oneend of a tear strip of the character dscribed which is simple andeiciently accomplished with a minimum of extra operations and equipment.

Numerous other .objects and advantages of the invention will 'be.apparent Aas it is better understood from: the following description,which, taken in connection with the accompanying drawings, discloses apreferred embodiment thereof.

The above objects are achieved by providing for a tubular containerbody, a metal end closure having an embossment located towards thecenter of the closure, which embossrnent provides in leffect anupstanding rivet extending lthrough -an .aperture in one end of a pulltab, the upper surface of the embossment being flanged or daredoutwardly over the periphery of the aperture to securely anchor the pulltab -to the end closure. The embossment is located in proximity to theinwardly extending ends of spaced score lines, the opposite ends ofwhich join or merge with a pair of spaced peripheral score lines in theclosure. Upon lifting of the pull tab these inwardly extending scorelines break through thereby releasing or freeing this end of the 4tearstrip defined by the score lines so that upon continued pulling of thepull tab the tear strip is progressively removed from the closure withthe resultant opening of the container.

Referring to the drawings:

FIGURE 1 is -a perspective view of a container having the end closuresof the instant invention;

FIGURE 2 is a sectional view taken substantially along line 2 2 ofFIGURE l;

Eile-,SF2 Patented Apr. 6, 1965 ICC FGURB 3 is a sectional view tak-ensubstantially along lines 3 3 of FIGURE l with the opening procedureshown in dot-dash lines;

FIGURE 4 is a fragmentary sectional view of the end closure immediatelyprior to the anchoring of the pull tab t-o the end; and

FIGURE 5 is an exploded View showing the end closure after removal fromthe can body.

As a preferred or exemplary embodiment of the instant invention, FIGUREl shows a tubular metal can body lll preferably circular lincross-section. Can body lll may be seamless such as being formed byimpact extrusion or may be -ormed by interlocking the marginal edges ofa llat blank in a manner well known to provide a longitudinal side seaml2. A lower end closure 14- is made integral with .the can body lileither by means of a conventional double seam i6 or in the case of animpacted extruded can, is of one piece with the can body lll. An upperend closure generally designated 18 is secured to the body lll by mea-nsof a conventional double seam 2i?.

The end closure iS comprises a countersunk central panel 22, which atits periphery merges with an opstanding countersink wall 24. Theoutermost periphery of the end 13 extends outwardly from the wall 24 tofro-rm a flange which is interfolded with a corresponding iiange on thecan body 1l) to form the seam 2li. A continuons score line 26 extendsaround the periphery of the panel 22 at the base of the wall 24. A scoreline 28 spaced concentrically inwardly from -the continuous score lines26 extends in a circular path in the panel 22; but, unlike the scoreline 26, does not join itself tor-ming a complete circle but ends at 29for reasons explained m-ore fully hereinafter. The score lines 26, 2Sform a iirst pair of score lines.

At one point 3@ in the length of the score line 25 a score line 32diverges or lforks from the score line 26 and extends radially inwardlytowards the center o-f the panel 22. A score line 311i continuing fromthe end of the score line 28 adjacent the point Sil also extendsradially inwardly towards the center of the panel 22 parallel with thesco-re line 32. A sco-re line 36 extending in a circular path around thecenter of the panel 22 connects the inner terminals of the score lines32, 3d.

It can thus be seen that the score lines 36, 34, 32, 2S and 26 define orenclose a removable area or tear strip 3S Within the panel 22. It is tobe understood that the inwardly extending pair of score lines 32, 3dneed not extend radially inwardly but could extend into the panel 22 atany desired angle. Further, the score line 36, in connecting the ends ofthe score lines 32, 34, need not be located in the center of the panel22 and may follow a path other than circular.

A iirst circular boss lib extends upwardly from the panel 22 andincludes the area for the most part enclosed by the score line 36. Aswith the score line 36, the boss lll may have a configuration other thancircular and need not be centrally located. However, this constructionis preferred because of ease of tooling, registration and production.The boss 4l) may be formed in any suitable manner, such as die-formingduring the formation of the end i3, or by drawing after the end 18 isinitially formed.

A second boss 42 extends upwardly from the center of the rst boss 4l).The boss 42 also may be struck from the end 13 by any suitable meanssuch as die-forming or drawing. Whether the boss 42 extends upwardlyfrom the boss 4) or from the unbossed panel 22 as mentioned hereinafter,it is essential to the instant invention that the boss 42 be locatedwithin the tear strip 3S adjacent the score line 36. Tins constructionis necessary to l permit rupture of the score line 36 during opening asexplained more fully hereinafter.

The boss 42 extends upwardly through an aperture 46 in one end of anelongated grasping or pull tab 4S. The

air/deva initial assembly of the pull tabV 48 on the boss 42 is shown inFIGURE 4. The pull tab 48 is located on the panel 22 so as to extendbeyond and substantially in alignment with the score lines 32, 34.

Tofirmly secure or anchor the pull tab 48 to the panel 22, the upper endof the boss 42 flares radially outwardly over'the periphery of theaperture 46. This outward liare of the boss 42 is readilyv accomplishedby swaging. To facilitate this swaging operation the center of the boss42 hasV therein'ra hollow depression 50 as shown in FIG- URE 4 Thedepression 50 is Vespecially desirable when theV end 18, including theboss 42, is composed of a relatively hard metal such as steel.

which is the preferred metal for the end 18, a depression 50 is notessential althoughit still facilitates the swaging operation.

As best shown in FIGURE 3 the free end 52 of the pull tab 48, i.e. theend remote from the aperture 46,'

is spaced from the panel 22. This spacing results from the mounting ofthe pull tab 48 on the first boss 40 with' its free end 52 extendingbeyond the periphery of the boss 40. This upward displacement of thefree end 52 of the tab 48 from the panel 22 provides a space into whichones iingers or a tool may enter to grasp thisV fining it. Score line 26being continuous or endless will continue to tear until the panel 22 iscompletely separated from the remainder of the end 18 along line 53.Score line 28,, however, endingV blind at 29' will cause the tear strip38 to remain attached to the panel 22. In this manner, when the scoreline 26 has completely torn through, the entire panel including thestrip 38 will be removed from the body as shown in FIGURE 5 to exposevthe canned product 54. l

l If desired, the first boss 40 may be omitted so that the pull tab 48lies ush with the surface ofthe panel 22. However, with such aconstruction, it is preferred to turn However, if the end 18V iscomposed of a'relatively soft Vmetal such'as aluminum,

the free end 52 of the tab 48 vupwardly'to facilitate grasp- Y ing ofthis end.

It is thought that the invention and many of its attendantadvantageswill be understood from the foregoingdescription and it will be apparentthat various changes maybe made inthe form, construction and arrangementof the 4parts without departing from the spirit and scopeof theinvention orsacrificing all of Vits material advantages, the formhereinbefore described being merely a preferred embodiment thereof.

I claim:

sealinglyengage one end of said body in an end seam, the f inner surfaceof said closure facing toward the interiorA of said body, a iirst pairof spaced Vscore lines surrounding at least a portion of said panel anddisposed adjacent said peripheral port-ion, a second pair of Vspacedscore lines continuing from said firstpair of score lines and extendinginwardly therefrom, aV single score line joining each of said secondpair of score lines at their inwardly' extending ends, said score' linesdefining a continuous tear strip within said panel,.and an elongatedpull tab secured at one end to said tear strip adjacent saidsingle scoreline; the improvement comprising a first boss ex.- tending outwardlyfrom the outer surface of said panel,

a second boss extending outwardly'frorn said first boss through anaperture inone end of said pull tab, the outermost surface of said.secondy boss being flared over the periphery of saidaperture to securesaid pull tab to said rst boss, the free Vend of said pull tab extendingbeyond said rst boss to provide aV space between said'free end and thesubjacent portion of saidpanel whereby said free end may be manuallygrasped and lifted toV break throughV said single score line and pulledto remove rsaid tear strip from said panel to open said container.

2. The end closure set forth in claim l wherein said above the level ofsaidpull tab and;

end seam extends said bosses. Y

3. The end closure set forth in claim 1 wherein said' single score lineextends arcuately around said first boss. 4. A metal end closure for acontainer comprisingi acentral panel; J a removable area within( saidpanel lines;V a first boss withinsaid area adjacent one of said scorelines;

an elongated pull tab having an'aperture adjacent one` end; and

a second boss extending outwardly from said first boss through saidapertureV and anged over the periphery of said aperture to secure saidone endof said pull tab toV said first boss'with theV other end of saidpull tabV being free and extending' beyond` theedge of said first bossto provide a space between` said free end and the subjacent portionof'said panel,

said pull tab adapted to be manually lifted to break; through said onescore line and pulled' toremovesaid removablev areaA from'said panel toopen said container.

References Cited by the Examiner UNITED STATES PATENTS Y 5/33v Prahl etal. V.. 2720-52 1,907,364 1,955,431 2,029,329 kLjungstrom et al 220-48Speidel 220-54 ,2,946,478 Clair etal; ..-'220-54 THERONE. CoNDoN,Primary Examiher, EARLE J. DaUMMoND, Examiner.

defined by `score Lymburner f 220'-52 Resef 220,-33

1. IN AN END CLOSURE FOR A CONTAINER HAVING A TUBULAR BODY, SAID ENDCLOSURE INCLUDING A CENTRAL PANEL, A PERIPHERAL PORTION INTEGRAL WITHSAID PANEL AND ADAPTED TO SEALINGLY ENGAGE ONE END OF SAID BODY IN ANEND SEAM, THE INNER SURFACE OF SAID CLOSURE FACING TOWARD THE INTERIOROF SAID BODY, A FIRST PAIR OF SPACED SCORE LINES SURROUNDING AT LEAST APORTION OF SAID PANEL AND DISPOSED ADJACENT SAID PERIPHERAL PORTION, ASECOND PAIR OF SPACED SCORE LINES CONTINUING FROM SAID FIRST PAIR OFSCORE LINES AND EXTENDING INWARDLY THEREFROM, A SINGLE SCORE LINEJOINING EACH OF SAID SECOND PAIR OF SCORE LINES AT THEIR INWARDLYEXTENDING ENDS, SAID SCORE LINES DEFINING A CONTINUOUS TEAR STRIP WITHINSAID PANEL, AND AN ELONGATED PULL TAB SECURED AT ONE END TO SAID TEARSTRIP ADJACENT SAID SINGLE SCORE LINE; THE IMPROVEMENT COMPRISING AFIRST BOSS EXTENDING OUTWARDLY FROM THE OUTER SURFACE OF SAID PANEL, ASECOND BOSS EXTENDING OUTWARDLY FROM SAID FIRST BOSS THROUGH AN APERTUREIN ONE END OF SAID PULL TAB, THE OUTERMOST SURFACE OF SAID SECOND BOSSBEING FLARED OVER THE PERIPHERY OF SAID APERTURE TO SECURE SAID PULL TABTO SAID FIRST BOSS, THE FREE END OF SAID PULL TAB EXTENDING BEYOND SAIDFIRST BOSS TO PROVIDE A SPACE BETWEEN SAID FREE END AND THE SUBJACENTPORTION OF SAID PANEL WHEREBY SAID FREE END MAY BE MANUALLY GRASPED ANDLIFTED TO BREAK THROUGH SAID SINGLE SCORE LINE AND PULLED TO REMOVE SAIDTEAR STRIP FROM SAID PANEL TO OPEN SAID CONTAINER.